A convenientroute to 2-lithio-1,3-butadiene from chloroprene via a 2-stannyl-1,3-butadiene is presented, and the regioselecdve additions to a variety of carbonyl groups are demonstrated.
Aryl-Substituted Cyclopropyl Acetylenes as Sensitive Mechanistic Probes in the Gold-Catalyzed Hydration of Alkynes. Comparison to the Ag(I)-, Hg(II)-, and Fe(III)-Catalyzed Processes
作者:Georgia Velegraki、Manolis Stratakis
DOI:10.1021/jo401325t
日期:2013.9.6
of vinyl carbocations, provides exclusively the corresponding cyclopropylmethylketones. On the other hand, in the Ag(I)- or Fe(III)-catalyzed hydration, a profound vinyl carbocationic character appears in the initially formed metal–alkyne complexes, as judged by the partial (Ag+) or exclusive (Fe3+) formation of allene-type rearrangement products. These findings provide clear evidence for subtle electronic
The reaction of 2-(1,3-butadienyl)magnesiumchloride (1) with aldehydes and ketones afforded a mixture of 1,3-dienyl alcohol (3) and 1,2-dienyl alcohol (4). The selective formation of another 1,3-dienyl alcohol (6) was observed when the Grignard reagent (1) was treated with epoxides. The latter reaction was applied to the synthesis of the sex attractant of a bark beetle.